[mindfulmonkey]

Google Identity is not going to be the right solution for integration with other AD/LDAP stores.

Really big companies will often have multiple AD/LDAP identity stores with enterprise grade provisioning systems (Sailpoint, Oracle Identity Manager) to keep accounts in sync.

This offering from Google is meant as a replacement for AD/Exchange(obviously) for companies that are mid-small. It also offers provisioning to other apps but only those that support SAML Just-In-Time provisioning. I did not immediately see a way to add custom apps to this (for provisioning), so might be limited to just the OOTB apps they provide (List: https://support.google.com/cloudidentity/topic/7661972)

Auth0 today offers SAML integrations and if the target system supports JIT Provisioning, it will work the same as google.

And just to clarify, Google's offering is 100% meant for internal users (employees, anyone that you'd give a Google Apps account to)